Fuel flow wise (hopefully the boat has a fuel flow meter), 3.5gph works out to be about 64hp, 5gph works out to be about 91hp. So that 300hp engine (that works out to be about 16.5gph) should last along time. I'll be curious to see the top speed of the boat-I'm guessing it will tickle the 11 knot mark. Good Luck, TomC

We're getting a long way from Bus Storage here but something less than 1.2 x the square root of the waterline length is kind of accepted as the most efficient cruise speed. So assuming a 45 foot waterline gives something under 8 knots as the most efficient speed and Tom's right, 3 or 4 knots above that is likely all that is achievable absent Clifford's twin 900 HP engines. In our own case we have a 37 foot waterline and our sweet spot for cruising is 6.2 knots. I can do that pretty well anywhere from about 1100 RPM up to 1500 RPM (twin 120 HP Lehmans). If I'm really going balls out we turn 2500 RPM and maybe get an honest 9 knots. I can't do less than about 4.2 knots with both engines turning - that's why water freight is so economical - as long as you are content to stay under hull speed (1.2 x the square root of the waterline) you can move a lot of weight for very little fuel.

Curiously enough though, there is a woman in our club who has a Donzi - maybe 35 feet - with roughly 900 HP between 2 engines. She cruises at 35 knots and can go past 40. Her fuel burn PER MILE is actually less than mine. Obviously her fuel burn per hour is way more than ours but per mile she can do better than we can.

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R.J.(Bob) EvansUsed to be 1981 Prevost 8-92, 10 spdCurrently busless (and not looking)My websiteOur weblogSimply growing older is not the same as living.

Thanks Bob I was going and try and explain that point I figured it and Sean would best me my 1/2 mile more

I could get down to 42 gals per hr burn but it took longer to get where you were headed,if you got use it lol I could get up around 35 or 36 knots at 2200 rpm but the 2 -V10's loved the fuel at those rpms

I'd sell the coach now if it was me, even at 20 to 25 cents on the dollar. I'd be ten years older, fuel is going to cost a good deal more, batteries deteriorate, tires age, hoses and seals age, many of those components that comprise the coach systems will have a harder time repairing as companies disappear, replacement coach parts will be even harder to obtain, ten years of rent, storage insurance, different interests, and by then you can get a 2012 Prevost or other conversion cheaper by then to replace it. Invest the money for a future replacement. I realize it is your heart and soul building it, but it is only rubber, metal, wood, etc. What do YOU think it will be realistically worth in ten years?

Thanks Sean for the update. I've seen the stabilizers on the big boats up close, i used to have a dive service (which sounds much better than "i used to scrape barnacles") All boats roll but those round bottom trawlers... but the good is that 7-8 knots constant will really eat up the miles. Even in Bermuda the fuel truck will come to the quay to sell fuel. Save your bucks for those port fees, its apparently a good source of revenue. i would bet with all the other stuff your good at you are scuba ready.To keep the hull clean, fins, light wet suit and mask/snorkle and get those Suction cups with handle, take one rubber off and save it, you'l move quicker with just one cup, 6'' plastic scraper for the intakes and props and lots of white/extra fine scrubbies to keep waterline clean. And nothing cuts line like a good cheep serated kitchen knife. Tie a light line to your weight belt and have at it haha. To keep this on topic, could you store it at a small airport under a canvas cover?

Years ago there was an outfit that made barges that you drove your motorhome onto with the front wheels on a turntable and your drive wheels on rollers powering the propeller. By getting a large enough barge, and adding a pointed end to it, Sean won't need to store the bus. Just "drive" all over the world with stops where the bus could be taken off and travel that country for a few weeks. Gets you thinking! Good Luck, TomC

Curiously enough though, there is a woman in our club who has a Donzi - maybe 35 feet - with roughly 900 HP between 2 engines. She cruises at 35 knots and can go past 40. Her fuel burn PER MILE is actually less than mine. Obviously her fuel burn per hour is way more than ours but per mile she can do better than we can.

You'd expect there to be less drag in planing mode than in displacement mode (and if you can get the boat up onto hydrofoils they'd be less still). The basic shape of the drag-versus-speed graph is more-or-less the same for all boats, with a big 'hump' when the boat is in forced-mode (faster than hull speed, but not yet on it's bow wave). Many boats never get beyond forced-mode of course, and in many ways giving those boats more power than they can use is just an exercise in wasting fuel.

Jeremy

PS - if you want to go fast, get a boat with sails. New sailing speed record set last week at 65 knots, and no diesel burnt at all (and, no, it wasn't a windsurfer)

"Hydraulic steering with emergency tiller" wow I don't know if I would want to dock thatwith using a tiller.

Probably easier to dock with a tiller than with no helm at all. I've wondered about this on our boat. The rudders are under the bed and it would be a major adventure to jury rig control if the helm ever failed. Its one of those things that you just kind of ignore and hope you never have to deal with.

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R.J.(Bob) EvansUsed to be 1981 Prevost 8-92, 10 spdCurrently busless (and not looking)My websiteOur weblogSimply growing older is not the same as living.